Fish is released into the river at the Xixi National Wetland Park in Xihu district, Hangzhou on Jan 20. [Photo/zj.zjol.com.cn]

 A total of 100,000 fish was released into the Xixi National Wetland Park in Hangzhou, capital of East China's Zhejiang province, on Jan 20, with the aim of purifying the water and maintaining the biological diversity.

The released species included spotted silver carp, silver carp, grass carp and black carp.

Fish is poured into a pond at Xixi National Wetland Park. [Photo/zj.zjol.com.cn]

Officials said that scheduled fish releases have not only helped improve the diversity of fish species but also enriched fishery resources.

The Xixi National Wetland Park has also planted many varieties of plants to improve the water quality of the main fairway.